BANKNOTE printer De La Rue was urged yesterday by its French takeover suitor to come clean over its relationship with the Reserve Bank of India.

Oberthur Technologies, whose £900million bid approach for De La Rue was turned down last month, said it believed relations between De La Rue and its main customer had been “materially impaired” after faulty bank­note paper was produced last summer.

De La Rue said in November that it could lose a top customer as a result of its production problems but has never revealed a name. Oberthur yesterday said it had “reason to believe” a recent tender for the supply of 16,000 tonnes of paper for the Reserve Bank of India had been awarded to four competitors of De La Rue. It called on De La Rue to “inform the market” if it was an unsuccessful participant in the tender or if it had been invited to tender.

Oberthur president Jean-Pierre Savare said “crucial questions need answering” but added that its 905p a share bid proposal, which took into account the loss of the Indian contract, still stood. De La Rue said its relationship with the customer concerned remained uncertain.